1. Technical Field
The present disclosure relates to a surgical fastener instrument for applying surgical fasteners to body tissue and, more particularly, relates to a surgical circular fastener instrument incorporating a mechanism to permit selective mounting and release of an anvil retainer and/or anvil relative to the fastener head of the instrument.
2. Description of Related Art
Anastomosis refers to the surgical joining of separate hollow tissue sections. Typically, an anastomosis procedure follows surgery in which a diseased or defective section of a hollow tissue or organ structure is removed, thus requiring the joining of the remaining end sections of the tissue. Depending on the particular procedure performed and/or other factors, the end sections of the tissue may be joined by circular anastomosis, e.g., end-to-end anastomosis, end-to-side anastomosis, or side-to-side anastomosis.
In a circular anastomosis procedure, a fastener instrument drives a circular array of fasteners or staples through each of two end sections of tissue to join the end sections in end-to-end relation, and simultaneously core any tissue within the newly joined sections to clear a passage therethrough. A conventional circular anastomosis instrument includes a handle, an elongated shaft and a fastener head or cartridge at the end of the elongated shaft. An anvil assembly including an anvil rod and an attached anvil head is mountable relative to the fastener cartridge. The tissue end sections are clamped between the anvil head and the fastener cartridge, and the instrument is actuated causing fasteners to be driven through the tissue end sections for crimping by the anvil head.